This invention is in the field of interactive display systems. Embodiments of this invention are more specifically directed to the pairing of a control device with the computer system that is displaying visible output.
The ability of a speaker to communicate a message to an audience is generally enhanced by the use of visual information, in combination with the spoken word. In the modern era, the use of computers and associated display systems to generate and display visual information to audiences has become commonplace, for example by way of applications such as the POWERPOINT presentation software program available from Microsoft Corporation. For large audiences, such as in an auditorium environment, the display system is generally a projection system (either front or rear projection). For smaller audiences such as in a conference room or classroom environment, flat-panel (e.g., liquid crystal) displays have become popular, especially as the cost of these displays has fallen over recent years. New display technologies, such as small projectors (“pico-projectors”), which do not require a special screen and thus are even more readily deployed, are now reaching the market. For presentations to very small audiences (e.g., one or two people), the graphics display of a laptop computer may suffice to present the visual information. In any case, the combination of increasing computer power and better and larger displays, all at less cost, has increased the use of computer-based presentation systems, in a wide array of contexts (e.g., business, educational, legal, entertainment).
A typical computer-based presentation involves the speaker standing remotely from the display system, so as not to block the audience's view of the visual information. Because the visual presentation is computer-generated and computer-controlled, the presentation is capable of being interactively controlled, to allow selection of visual content of particular importance to a specific audience, annotation or illustration of the visual information by the speaker during the presentation, and invocation of effects such as zooming, selecting links to information elsewhere in the presentation (or online), moving display elements from one display location to another, and the like. This interactivity greatly enhances the presentation, making it more interesting and engaging to the audience.
The ability of a speaker to interact, from a distance, with displayed visual content, is therefore desirable. More specifically, a hand-held device that a remotely-positioned operator could use to point to, and interact with, the displayed visual information is therefore desirable.
U.S. Patent Application Publication US 2011/0227827, published Sep. 22, 2011 and entitled “Interactive Display System”, based on commonly assigned and copending application Ser. No. 13/025,015, Feb. 10, 2011, incorporated herein by reference, describes an interactive display system including a wireless pointing device including a camera or other video capture system. The pointing device captures images displayed by the computer, including one or more human-imperceptible positioning targets. The location, size, and orientation of the recovered positioning target identify the aiming point of the remote pointing device relative to the display. Temporal sequencing of the positioning targets (either human-perceptible or human-imperceptible) to position the pointing device is also described.
As is well known in the art, point-to-point communication over a conventional short-range wireless (e.g., “Bluetooth”) channel involves the “pairing” of the two devices that are to communicate with one another. To summarize, conventional pairing involves the recognition of each device by the other device, and authentication in the sense that each device “trusts” the communications received from the other over the short-range wireless channel. Such pairing addresses the issue that conventional short-range wireless devices transmit and receive omnidirectionally. As such, a receiving device may receive wireless signals from devices other than the intended transmitter. Pairing avoids confusion by enabling each device to respond to wireless signals only from its intended transmitting devices, and to have its transmitted signals responded to only by its intended receiving devices.
Of course, certain applications will require some level of security in these wireless communications. In those cases, the pairing process will also include the exchange of encryption keys, so that each of the paired devices can encrypt and decrypt its wireless communications.
Conventional pairing techniques for short-range wireless communication with computer systems often incorporates “out-of-band” techniques (i.e., using both wireless communication and communication by some means other than wireless) to establish the paired relationship. These conventional techniques require each of the paired devices to authenticate the other—in other words, the device initiating the pairing authenticates the responding device, and the responding device also authenticates the initiating device.
In the context of an interactive display system, such as that described in the above-incorporated U.S. Patent Application Publication US 2011/0227827, the pairing of a pointing device with the computer system or graphics subsystem displaying and controlling the displayed output, presents a different situation from that of conventional short-range wireless communications. More specifically, the display system with which communication is desired may be deployed within wireless range of other display systems, such as in different conference rooms or classrooms. While the presenter is only interested in controlling the display system visible to him, the wireless signal transmitted by his pointing device may reach display systems in other rooms within wireless signal range. Conversely, the display system he wishes to control may be receiving control signals from pointing devices in those nearby rooms. As such, some level of pairing is necessary to avoid interference at the desired display system from other pointing devices. However, it is contemplated that the pointing device may not be nominally assigned to a particular display system but may instead belong to the presenter for use with different systems, at different locations, and at different times. For example, the pointing device may belong to a salesman for use in presentations at various customers. In that context, the ability to rapidly and easily pair pointing devices with display systems is useful. Furthermore, it is highly desirable for the pointing device to be simple in its construction and operation, with only one or two buttons (e.g., similar to a computer mouse) to attain a relatively small form factor, and with minimum RF transmission capability to conserve battery power.